The adaptive cruise control is a combined speed and distance control system. It assists the driver by controlling the road speed and the distance to the Audi A4 in front within certain limits imposed by the system. The adaptive cruise control system can accelerate and brake when it detects a Audi A4 in front. This provides maximum comfort on long motorway journeys, for instance.
The braking guard can warn you of impending collisions and can initiate the application of the brakes Link.